Systems and Methods for Simulating Depth of Field on a Computer Generated Display

1. A system for simulating depth of field in a computer graphics display, comprising: an image generation circuit configured to generate an image representing a plurality of objects for display on the computer graphics display, wherein the image generation circuit is configured to generate the image using a single blur parameter for each of the plurality of objects that represents both a magnitude of blur and a relative distance with respect to a lens focal distance being simulated by the image generation circuit; wherein the relative distance represents whether the object is in a far-field, in-focus, or near-field position with respect to the focal distance; wherein the blur parameter is a base blur parameter value for in-focus objects, a higher value than the base blur parameter value for far-field objects, and a lower value than the base blur parameter value for near-field objects.

2. The system of claim 1 , wherein the blur parameter is a positive value for far-field objects and a negative value for near-field objects.

3. The system of claim 1 , wherein the computer graphics display is part of a flight simulation system.

4. The system of claim 1 , wherein the image is generated using a single rendering pass and without the use of either ray tracing or accumulation buffers.

5. A system for simulating depth of field in a computer graphics display, comprising: an image generation circuit configured to generate an image representing a plurality of objects for display on the computer graphics display, wherein the image generation circuit is configured to generate the image using a single blur parameter for each of the plurality of objects that represents both a magnitude of blur and a relative distance with respect to a lens focal distance being simulated by the image generation circuit; wherein the relative distance represents whether the object is in a far-field, in-focus, or near-field position with respect to the focal distance; wherein the blur parameter is a base blur parameter value for in-focus objects, a lower value than the base blur parameter value for far-field objects, and a higher value than the base blur parameter value for near-field objects.

6. The system of claim 5 , wherein the blur parameter is a negative value for far-field objects and a positive value for near-field objects.

7. A method of anti-aliasing an image, the image having a plurality of pixels and a plurality of objects represented therein, comprising: using an image generation circuit to generate an image representing the plurality of objects for display on the computer graphics display; using properties of the objects to retrieve a blur value and a relative distance for each of a plurality of subpixels of each pixel, wherein the relative distance represents whether an object associated with the subpixel is in a far-field, in-focus, or near-field position with respect to a focal distance of the image; determining an anti-aliasing output for one or more pixels based on the blur values and relative distances of the subpixels of the pixel, wherein the anti-aliasing output for each pixel is determined using a non-averaging method such that the blur values of the subpixels are not averaged to determine the anti-aliasing output of the pixel; and providing the determined anti-aliasing output for each pixel; wherein the anti-aliasing output is a base anti-aliasing output for pixels associated with in-focus objects, a lower value than the base anti-aliasing output for pixels associated with far-field objects, and a higher value than the base anti-aliasing value for pixels associated with near-field objects.

8. The method of claim 7 , further comprising: determining an anti-aliasing color output for each pixel using an averaging method such that color values of the subpixels of the pixel are averaged to determine the anti-aliasing color output of the pixel.

9. The method of claim 7 , wherein the determined anti-aliasing output for each pixel is a blur value for the pixel.

10. The method of claim 9 , wherein determining a blur value for each pixel comprises selecting the blur parameter of a subpixel that is associated with a closest position of the plurality of subpixels of the pixel within a field of view of the image.

11. The method of claim 9 , wherein determining a blur value for each pixel comprises selecting a blur parameter associated with a greatest number of subpixels from among the plurality of subpixels of the pixel.

12. The method of claim 7 , wherein blur value and relative distance are represented using a single blur parameter.

13. The method of claim 7 , wherein the image is displayed on a flight simulation system.

14. The method of claim 7 , wherein the anti-aliasing output is a blur parameter representing both the blur value and the relative distance.